Harnessing the MERP community to understand cumulative effects on marine ecosystems

Published: 01 September 2017

The MERP community of researchers and stakeholders encompasses an impressive range of knowledge and understanding of the UK’s marine ecosystems. To address many of the more ecological questions that interest us, we tend to apply this knowledge via a range of scientific and technical routes, typically using some combination of theory and data, statistical and mathematical modelling, observation and experiment.

However, as we venture into more complex questions, particularly those questions which combine ecological systems with the social and political systems of management, we start to hit limitations in these techniques. An option being explored throughout MERP is to improve our methods to handle more complex cases and to complement this, we can also think about drawing on our community’s knowledge and understanding in less orthodox ways. This is something we are exploring in our 'Cumulative Effects' work in Work Package 3, where we are trying to understand the effects of multiple management options on multiple indicators of ecosystem state.

Part of the challenge here is to re-cast ecological questions in terms that have more immediate management relevance. We are doing this by focusing on well-established indicators of ecosystem state, already been adopted by organisations, such as OSPAR, which can be derived from the ecological data we have been collating within MERP’s Work Package 1, such as abundance and body size. We then think about responses of these indicators to a range of possible impacts, adopting methods used in risk assessment to create chains of impact from causes (‘hazards’) to consequences (ecological effects), describing how these will be affected by preventative or mitigating management actions.

Tracing how these chains of impact interact i.e. how multiple impacts and managment actions combine to affect ecosystem indicators, benefits from data but often we lack appropriate data to fully quantify the network models we are building. Fortunately, the methods we employ are flexible and allow us to incorporate more qualitative information, including the subjective expert judgements of the MERP researcher and stakeholder communities, regarding the likely form of individual relationships and their interactions.

At present, we are busy preparing for our first major stakeholder workshop to apply these methods to our Cardigan Bay case study. Working with our stakeholders we will use this to test and refine methods, which in turn will help us to incorporate expert knowledge into our models of the ecological and management system, and explore how we can effectively communicate the outputs of these models in a form that is useful to decision makers. Building on ongoing work on expert elicitation and effective visual communication of complex model ouputs within MERP, we will be able to help with the challenging task of assessing the cumulative effects of mutliple impacts and management actions on our marine ecosystems.